This invention relates to the use of hydroxybutyrate and poly-hydroxybutyrate as components of animal feed or drinking water or feed or drinking water additives, as well as to compositions, feed additives, drinking water and feed containing them.
The term feed or feed composition means any compound, preparation, mixture, or composition suitable for, or intended for intake by an animal.
More particular, the present invention relates to the use of 3-hydroxybutyrate (HB) or a salt, ester, or combination of HB, a HB salt and a HB ester, or poly-3-hydroxybutyrate (PHB) or a salt, ester, or combination of PHB, a PHB salt and a PHB ester as active ingredients of nutraceutical compositions for animals.
The term “nutraceutical” as used herein denotes a usefulness in both the nutritional and pharmaceutical field of application. Thus, the nutraceutical compositions can find use as a complete animal feed (diet), as supplement to animal feed, and as pharmaceutical formulations for enteral or parenteral application which may be solid formulations, or liquid formulations.
The term animal includes all animals including human. Examples of animals are non-ruminants, and ruminants. Ruminant animals include, for example, animals such as sheep, goat, and cattle, e.g. cow such as beef cattle and dairy cows. In a particular embodiment, the animal is a non-ruminant animal. Non-ruminant animals include pet animals, e.g. horses, cats and dogs; mono-gastric animals, e.g. pig or swine (including, but not limited to, piglets, growing pigs, and sows); poultry such as turkeys, ducks and chickens (including but not limited to broiler chicks, layers); fish (including but not limited to salmon, trout, tilapia, catfish and carp); and crustaceans (including but not limited to shrimp and prawn).
In farm animals suppression of enteric diseases on one hand and growth promotion on the other hand have been achieved by the inclusion of antibiotics and/or chemotherapeutics into the diets.
On the one hand, butyric acid is known as a “soft” antimicrobial which shows a “prebiotic” effect when treated to animals. Butyric acid has a strong positive effect on the enterocytes and colonocytes proliferation and maturation. Currently butyric acid is added (mostly together with antibiotics) to animal feed as prebioticum after it is synthesized, neutralized with CaO and worked up with silicate. But one of the big disadvantages of using butyric acid in animal nutrition is that the current butyric acid products are sticky and smell very bad.
On the other hand, in recent years, considerable attention has been also paid to short chain fatty acids (SCFAs) as an alternative to traditional growth promoters. For example European patent application 1′661′574 discloses a composition comprising polymers of short to medium chain hydroxy fatty acids, hereinafter also called “Polyhydroxyalkanoates (PHAs)”, which are used for delivering the hydroxy fatty acid or an oligomer thereof to the large intestine. In case the composition is administrated orally, the composition will be delivered to the large intestine, without being degraded in the stomach or short intestine, but being degraded by the large intestinal bacterial flora resulting in the release of the short to medium chain fatty acids or oligomers thereof. EP 1′661′574 further discloses that the released short to medium chain fatty acids or oligomers thereof have useful physiological activities and are effective for treating or preventing inflammatory diseases or cancer in the large intestine.